1. Field of the Invention
This invention relates to 2-hydroxybenzotriazol compounds and also to the use thereof.
2. Description of Prior Art
It is known that many polymers are degraded by the action of ultraviolet light. Polyolefins, polyesters, polyamides and the like are examples of polymers which deteriorate when exposed for a long time to ultraviolet light, e.g. sunlight.
Recently a variety of goods including foods such as refreshing drinks, alcoholic drinks edible oils, cosmetics, and medicines have been sold and stored in transparent plastic containers. Since ultraviolet light with a wavelength of about 250 to about 390 nm passes freely through such transparent plastic containers, the contents are subject to deterioration, discoloration and decomposition.
It is known that cyanoacrylate ultraviolet absorbers can be incorporated in the above-mentioned polymers for the purpose of protecting the polymers and the contents of the plastic containers from deterioration from ultraviolet light (cf. U.S. Pat. No. 4,617,374). It is also known that the incorporation by mixing or by copolymerization of benzotriazol ultraviolet absorbers in polymers can give ultraviolet absorptive capacity to the polymers (cf. Japanese Patent Publication No. 35221/1982 and U.S. Pat. No. 3,214,436).
However, cyanoacrylate ultraviolet absorbers are inferior to benzotriazol ultraviolet absorbers both in thermal stability and ultraviolet absorption. Further, the polymers obtainable by copolymerization of the benzotriazol ultraviolet absorbers described in the above-mentioned Japanese Patent Publication No. 35221/1982 have poor thermal resistance and have unsatisfactory ultraviolet absorbability. Polymers obtainable by copolymerization of the benzotriazol compound described in U.S. Pat. No. 3,214,436 have unsatisfactory ultraviolet absorbability.
Accordingly, an object of the present invention is to provide a novel 2-hydroxyphenylbenzotriazol compound having excellent ultraviolet absorptive capacity.
Another object of the invention is to provide the use of the novel 2-hydroxyphenylbenzotriazol compound as an ultraviolet absorber.
Still another object of the invention is to provide a polymer having excellent ultraviolet absorbability obtainable by incorporation of the novel 2-hydroxyphenylbenzotriazol compound.
Yet another object of the invention is to provide a polymer having excellent ultraviolet absorbability obtainable by copolymerization of the novel 2-hydroxyphenylbenzotriazol compound.
These objects as well as other objects and advantages of the present invention will become apparent to those skilled in the art from the following detailed description.